| Abstract Scope |
Aluminum nitride (AlN) is a piezoelectric wide band-gap semiconductor with excellent thermal properties. AlN parts are usually sintered, but laser powder bed fusion can enable microstructural engineering, defect control, and potentially improve performance. However, under ambient conditions, AlN will decompose into diatomic nitrogen gas and aluminum instead of melting, though this decomposition has been suppressed in reported literature by increasing the partial pressure of nitrogen gas in the system. Additionally, a prior report shows some melting of AlN by laser irradiation in an argon environment. This work describes LPBF work on AlN that has shown clear signs of melting under both argon and nitrogen environments. This melting is not seen in all samples, indicating the importance of process parameter control. The project seeks to understand how congruent melting of the nitride can occur and how it can be promoted over the equilibrium decomposition reaction. |